UI (and crosshairs) stretched when playing 3440x1440

Those two settings already exist in my video config. 21:9 is in the video menu in game, it's several UI elements that don't scale properly.

For example, the "[F] Mute Teammates" on the game loading screen is stretched, but once in hero pick it scales correctly (i.e. the exact same text appears stretched and then in proper aspect ratio in different areas of the game). This is a coding issue, not simply a config issue.